Batman: Arkham: Killer Croc collection, and you can see similar discussion beginning to build at the online retailers, too. It seems the book collects the first three parts of Croc's four-part first "major" appearance, but omits that fourth part.
Killer Croc had shadowed appearances in Gerry Conway's 1980s Detective Comics #523 and Batman #357, but hist first "named" appearance is in Batman #358. That's a four-part story, Batman #358 and 359 with Detective Comics #525 and #526, but Detective #526 isn't included in the book. It's definitely "part four"; Batman #359 ends with "to be concluded ... in Detective #526" (the trade even includes this language). All of this is also the story, by the way, where the pre-Crisis on Infinite Earths (blond) Jason Todd becomes Robin, with Detective #526 being the one where he puts on a Robin costume.
So why isn't the issue included in Batman: Arkham: Killer Croc? Well, it is an extra-sized issue (marking Batman's 500th appearance), so maybe the size has something to do with it. I don't know if it's a matter of not wanting to include an extra artist in the trade, though the issue is still written by Conway. There are plenty of villains in that particular issue who are not Croc, but then again Croc does also figure heavily in the story.
I do note that neither the solicitation for the book nor the book itself says that it includes Detective #526 -- that doesn't make the reading experience better, I understand, but it doesn't look like an instance of a misprint necessarily (the issue wasn't promised to be delivered). At the same time, the omission does give me pause about picking up the book -- I have tended to avoid those dedicated writer/artist collections because they skip around issues, and for me this would kind of be the same thing. The issue is in Greatest Batman Stories Ever Told Vol. 2, though I don't think readers were expecting to have to pick up an additional book.
Did you snag this collection? How does this news make you feel about it?